logiguard fork: GPUI xdg-activation keyboard-focus serial fix

Single-commit orphan branch: full zed-industries/zed @ 8c74db0 source tree
with a 3-file patch applied (no upstream history).

Patch (crates/gpui_linux/src/linux/wayland/):
  - serial.rs: add SerialKind::KeyboardEnter
  - client.rs: store wl_keyboard.enter serial; add latest_serial_of()
  - window.rs: activate() uses keyboard-enter serial (Mutter focus gate)

Mutter honors window activation only when the token carries the keyboard-
focus serial from wl_keyboard.enter; GPUI used a stale mouse-press serial.
See docs/tray-window-focus-wayland.md in logiguard.

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>

crates/gpui/examples/focus_visible.rs

@@ -0,0 +1,229 @@
+#![cfg_attr(target_family = "wasm", no_main)]
+
+use gpui::{
+    App, Bounds, Context, Div, ElementId, FocusHandle, KeyBinding, SharedString, Stateful, Window,
+    WindowBounds, WindowOptions, actions, div, prelude::*, px, size,
+};
+use gpui_platform::application;
+
+actions!(example, [Tab, TabPrev, Quit]);
+
+struct Example {
+    focus_handle: FocusHandle,
+    items: Vec<(FocusHandle, &'static str)>,
+    message: SharedString,
+}
+
+impl Example {
+    fn new(window: &mut Window, cx: &mut Context<Self>) -> Self {
+        let items = vec![
+            (
+                cx.focus_handle().tab_index(1).tab_stop(true),
+                "Button with .focus() - always shows border when focused",
+            ),
+            (
+                cx.focus_handle().tab_index(2).tab_stop(true),
+                "Button with .focus_visible() - only shows border with keyboard",
+            ),
+            (
+                cx.focus_handle().tab_index(3).tab_stop(true),
+                "Button with both .focus() and .focus_visible()",
+            ),
+        ];
+
+        let focus_handle = cx.focus_handle();
+        window.focus(&focus_handle, cx);
+
+        Self {
+            focus_handle,
+            items,
+            message: SharedString::from(
+                "Try clicking vs tabbing! Click shows no border, Tab shows border.",
+            ),
+        }
+    }
+
+    fn on_tab(&mut self, _: &Tab, window: &mut Window, cx: &mut Context<Self>) {
+        window.focus_next(cx);
+        self.message = SharedString::from("Pressed Tab - focus-visible border should appear!");
+    }
+
+    fn on_tab_prev(&mut self, _: &TabPrev, window: &mut Window, cx: &mut Context<Self>) {
+        window.focus_prev(cx);
+        self.message =
+            SharedString::from("Pressed Shift-Tab - focus-visible border should appear!");
+    }
+
+    fn on_quit(&mut self, _: &Quit, _window: &mut Window, cx: &mut Context<Self>) {
+        cx.quit();
+    }
+}
+
+impl Render for Example {
+    fn render(&mut self, _window: &mut Window, cx: &mut Context<Self>) -> impl IntoElement {
+        fn button_base(id: impl Into<ElementId>, label: &'static str) -> Stateful<Div> {
+            div()
+                .id(id)
+                .h_16()
+                .w_full()
+                .flex()
+                .justify_center()
+                .items_center()
+                .bg(gpui::rgb(0x2563eb))
+                .text_color(gpui::white())
+                .rounded_md()
+                .cursor_pointer()
+                .hover(|style| style.bg(gpui::rgb(0x1d4ed8)))
+                .child(label)
+        }
+
+        div()
+            .id("app")
+            .track_focus(&self.focus_handle)
+            .on_action(cx.listener(Self::on_tab))
+            .on_action(cx.listener(Self::on_tab_prev))
+            .on_action(cx.listener(Self::on_quit))
+            .size_full()
+            .flex()
+            .flex_col()
+            .p_8()
+            .gap_6()
+            .bg(gpui::rgb(0xf3f4f6))
+            .child(
+                div()
+                    .text_2xl()
+                    .font_weight(gpui::FontWeight::BOLD)
+                    .text_color(gpui::rgb(0x111827))
+                    .child("CSS focus-visible Demo"),
+            )
+            .child(
+                div()
+                    .p_4()
+                    .rounded_md()
+                    .bg(gpui::rgb(0xdbeafe))
+                    .text_color(gpui::rgb(0x1e3a8a))
+                    .child(self.message.clone()),
+            )
+            .child(
+                div()
+                    .flex()
+                    .flex_col()
+                    .gap_4()
+                    .child(
+                        div()
+                            .flex()
+                            .flex_col()
+                            .gap_2()
+                            .child(
+                                div()
+                                    .text_sm()
+                                    .font_weight(gpui::FontWeight::BOLD)
+                                    .text_color(gpui::rgb(0x374151))
+                                    .child("1. Regular .focus() - always visible:"),
+                            )
+                            .child(
+                                button_base("button1", self.items[0].1)
+                                    .track_focus(&self.items[0].0)
+                                    .focus(|style| {
+                                        style.border_4().border_color(gpui::rgb(0xfbbf24))
+                                    })
+                                    .on_click(cx.listener(|this, _, _, cx| {
+                                        this.message =
+                                            "Clicked button 1 - focus border is visible!".into();
+                                        cx.notify();
+                                    })),
+                            ),
+                    )
+                    .child(
+                        div()
+                            .flex()
+                            .flex_col()
+                            .gap_2()
+                            .child(
+                                div()
+                                    .text_sm()
+                                    .font_weight(gpui::FontWeight::BOLD)
+                                    .text_color(gpui::rgb(0x374151))
+                                    .child("2. New .focus_visible() - only keyboard:"),
+                            )
+                            .child(
+                                button_base("button2", self.items[1].1)
+                                    .track_focus(&self.items[1].0)
+                                    .focus_visible(|style| {
+                                        style.border_4().border_color(gpui::rgb(0x10b981))
+                                    })
+                                    .on_click(cx.listener(|this, _, _, cx| {
+                                        this.message =
+                                            "Clicked button 2 - no border! Try Tab instead.".into();
+                                        cx.notify();
+                                    })),
+                            ),
+                    )
+                    .child(
+                        div()
+                            .flex()
+                            .flex_col()
+                            .gap_2()
+                            .child(
+                                div()
+                                    .text_sm()
+                                    .font_weight(gpui::FontWeight::BOLD)
+                                    .text_color(gpui::rgb(0x374151))
+                                    .child(
+                                        "3. Both .focus() (yellow) and .focus_visible() (green):",
+                                    ),
+                            )
+                            .child(
+                                button_base("button3", self.items[2].1)
+                                    .track_focus(&self.items[2].0)
+                                    .focus(|style| {
+                                        style.border_4().border_color(gpui::rgb(0xfbbf24))
+                                    })
+                                    .focus_visible(|style| {
+                                        style.border_4().border_color(gpui::rgb(0x10b981))
+                                    })
+                                    .on_click(cx.listener(|this, _, _, cx| {
+                                        this.message =
+                                            "Clicked button 3 - yellow border. Tab shows green!"
+                                                .into();
+                                        cx.notify();
+                                    })),
+                            ),
+                    ),
+            )
+    }
+}
+
+fn run_example() {
+    application().run(|cx: &mut App| {
+        cx.bind_keys([
+            KeyBinding::new("tab", Tab, None),
+            KeyBinding::new("shift-tab", TabPrev, None),
+            KeyBinding::new("cmd-q", Quit, None),
+        ]);
+
+        let bounds = Bounds::centered(None, size(px(800.), px(600.0)), cx);
+        cx.open_window(
+            WindowOptions {
+                window_bounds: Some(WindowBounds::Windowed(bounds)),
+                ..Default::default()
+            },
+            |window, cx| cx.new(|cx| Example::new(window, cx)),
+        )
+        .unwrap();
+
+        cx.activate(true);
+    });
+}
+
+#[cfg(not(target_family = "wasm"))]
+fn main() {
+    run_example();
+}
+
+#[cfg(target_family = "wasm")]
+#[wasm_bindgen::prelude::wasm_bindgen(start)]
+pub fn start() {
+    gpui_platform::web_init();
+    run_example();
+}